> Manipulating chess pieces is trivial for e.g. a pick and place robot,

Perhaps in a sterile, well-known, controlled environment; but not in a real world, novel, potentially adversarial environment.

I guess my point is about AGI is that I would bet a 7-year old could currently beat the best AI in the world at real, physical chess, played in a randomly chosen park. Kids can quickly figure out strategies in the real world with its more degrees of freedom than you have in the digital world of computer chess. In other words, perhaps a kid may figure out that if they place a piece in a certain position, the computer is unable to "see" or "execute" the desired move, perhaps because the angle of the sun or some line of sight obstruction. While an adult might be generous and offer help, a lot of children will take advantage of the robot's weaknesses.